As we welcome the spiced lattes and crisp leaves of Fall, we also enter into the throes of cold and flu season, where every doorknob and elevator button becomes an obstacle in the battle to stay sniffle-free. Current estimates project that Americans will come down with about half a billion (yes, that's a "b") colds this year, and anywhere between five to 20 percent of the population will develop the dreaded flu.

But salvation is possible, and it comes in the form of prevention. Here, we round up every science-backed method that has been shown to stop the spread of cold and flu viruses long before they cause illness.